TheRPGSite

This thread is for declaring the ultimate supremacy of your favorite mathematically equivalent resolution system.  Now stop shitting up the RQ6 thread. :D

roll-over = Rolemaster
roll-under = Runequest

Both are good.

I find roll over more intuitive.

Quote from: CRKrueger;468509This thread is for declaring the ultimate supremacy of your favorite mathematically equivalent resolution system.  Now stop shitting up the RQ6 thread. :D

I prefer roll under. It makes the chance easy to understand at glance since I deal with percent chance of x happening almost every day. Roll over can be  mathematically equivalent, but it is less intuitive -- at least for me.

I really don't give a fuck whether it's roll-over or roll-under as long as the system works.

Quote from: HombreLoboDomesticado;468514I really don't give a fuck whether it's roll-over or roll-under as long as the system works.

This.

I'm a huge fan of houseruling for the sake of fine-tuning a game.

I'm not a fan of houseruling for the sake of houseruling.

I actually like roll 1d100, add bonuses(skill level) and try to get a target number, like "100"...

Well, the percentile games I've designed are all roll under so I guess that's my preferance.  I love Rolemaster but too many people have trouble doing double digit math.

Mind you, roll between is closer to my favorite though it still breaks down.  Roll under skill roll over difficulty is essentially the same as roll under skill - difficulty and only becomes more complex when difficulty exceeds skill or skill exceeds 100.

Roll over is strictly superior the moment you:

• Have modifiers.
• Have opposed tests.
• Have to calculate degree of success.

If you are literally always applying a pass/fail test against your unmodified skill check, then Roll Under is a little bit easier. The very moment that a circumstantial modifier could change your chances or you'd be asked to compare the amount you succeeded by to another character or to a chart, then Fixed TN 100 is demonstrably the superior option.

In Fixed TN 100 your modifiers and results get added together into a single number, which means that if you forget a modifier or have to compare values that the player only has to report one number. In roll under, you have two different numbers to keep track of (modified skill and roll), or you collapse it into a single number by replacing addition with subtraction that demonstrably takes more time to complete. Either way, TN 100 is faster and better at resolution.

There are basically two ways for Roll Under to generate degree of success. The first is "Blackjack", where the literal number you roll is your degree of success if it is under your TN and a failure if it is not. This has the advantage of being relatively fast, since actual resolution is just a comparison and your degree of success is the unmodified number on the dice. Unfortunately, that bogs down severely when you have skill modifiers, because you have to report and modify your skill number separately from reporting your actual roll and if you forget a modifier you have to remember both the literal roll and the modified skill (since "I missed by 3" is actually meaningless information in such a system). The second way to generate degree of success in roll under is "subtract roll from modified skill". This doesn't have the multi-reporting issue, but the procedure is literally exactly the same as Fixed TN 100 except that it uses subtraction instead of addition, which is a provably slower operation when used by real people at the table.

This isn't a thing where we agree to disagree or where both sides have points. It's mathematically equivalent and Fixed TN 100, Roll High is provably superior. It has the positive qualities of both the Blackjack and Subtraction methods of calculating degree of success. And no additional disadvantages. If you support Roll Under, you are a grognard. You are someone who is willing to use a demonstrably and demonstratedly inferior system just because it was "good enough" in the 1970s. I genuinely feel sorry for people who continue to support d100 Roll-Under.

-Frank

I'm gonna need some examples, there.

Quote from: Vile;468540I'm gonna need some examples, there.

Fair enough.

Let's say you have a skill of 60. Regardless of what you do, the system is going to output that you succeed 60% of the time, because that is what a d100 is for. Also, if you have a -10% modifier, you will succeed 50% of the time. Now there are three ways to get degrees of success out of this:

[size=14]Blackjack[/size]
In the Blackjack system, a roll that is more than your modified skill is a failure, and a roll that is less than your modified skill has a success value equal to the number rolled. This is relatively fast to generate degrees of success, but you have to track and report both the literal roll and your modified skill separately in case you missed something or the GM wants to spring something on you.

So you roll a 59. Your degree of success is "59", unless you have a penalty that lowers your modified skill to less than 59, in which case your roll is a "failure". But you still end up subtracting the roll from the skill to determine whether modifiers would matter, and then you have to track the number of how much you made or failed the roll by and the literal number you rolled separately if you want the ability to retroactively add a modifier. So a 59 is "very good" if your modified skill is 59 or better, and "very bad" if not.

[size=14]Subtraction[/size]
In the subtraction system, your degree of success is the modified skill minus the literal roll on the dice. This has the advantage that a good roll is always good (00 is a degree of success equal to your modified skill). And it has the advantage that it has one reporting number that can be further modified by new modfiers as you think of them. However, a near miss that you're looking for a positive modifier to push over the top is a negative number and in any case the core mechanic is one of subtraction - which is just like addition mathematically but is substantially harder for people to actually do in practice.

In the subtractive system a roll of 59 is always pretty bad, and it gives a result of "1" if you have a skill of 60 and a result of "-9" if you have a -10 penalty at the time.

[size=14]TN 100[/size]
In the TN 100 system, you add the roll to your modified skill. Your target number is 100, and your "degree of success" is simply the actual result (2-digits degrees of success are failures). This has the unity of result and success that Blackjack provides and it has the single reported result that Subtraction does.

In the TN 100 system, you roll a 59 and add 60 and get 119. If you have a -10 penalty you need to add, it goes down to 109. But your numbers stay positive all the time and you don't need to track more than one number for reporting purposes.

-Frank

Quote from: FrankTrollman;468545Let's say you have a skill of 60. Regardless of what you do, the system is going to output that you succeed 60% of the time, because that is what a d100 is for. Also, if you have a -10% modifier, you will succeed 50% of the time. Now there are three ways to get degrees of success out of this:

Two points:

1) In many games, you don't need a get degree of success out of the roll.

2) There's a fourth method. The one Chaosium Runequest (and other BRP-based games use). Special/Impale and critical successes are a percentage of your chance of success -- and are looked up on a table so you don't need to do any math at all to determine them.

Quote from: RandallS;468565Two points:

1) In many games, you don't need a get degree of success out of the roll.

2) There's a fourth method. The one Chaosium Runequest (and other BRP-based games use). Special/Impale and critical successes are a percentage of your chance of success -- and are looked up on a table so you don't need to do any math at all to determine them.

If they are a "percentage of your chance to succeed", that would normally be a form of math. Of course, there are better ways to do that too. For example, rather than dividing your modified skill by 10 (or 5), just assign one number (or 2) in the ones place to be the critical threat. If you got the magic number and you succeeded, it's a crit.

Doing that is just like the roll under "divide your modified skill by X" system except that it is more forgiving if you have a modifier you need to add later (since you never need to "redo" the division because you never had to do any division) and it's faster all the time because you never have to do a division step.

The basic mechanics of most d100 systems are old and clunky and they can be improved without loss of functionality by embracing modern, streamlined mechanics.

-Frank

Okay, if I'm getting this straight, the main difference is that with roll-over you have a fixed target (always 100), while with roll-under the target moves for every situation. Both systems use modifiers. That seems a simplification to me on first reading.

D100 uses degrees of success based on a fraction of the chance. Maths needed if you don't use the table, although you learn the numbers pretty quickly if you game regularly. Roll over would need a similar system to create, say, criticals.

The opposed roll degree of success thing also works pretty much the same with both systems. Basically, the higher successful roll wins.

I can see I'll be looking into this in more detail. It might be worth adopting roll-over in a new game, but not for an established TM that has certain fundamental expectations attached to it. Assuming the roll-over tops roll-under, the difference does not seem to justify changing an established system, either from the (re)writing effort or customer expectation perspective.

Now, a new game ... TNQuest ... TNQ ... TaNQ, a future game of sentient armoured bolos! Are there actually any games out there that use Roll-over D100 (given that I can't stand Rolemaster)?

Quote from: FrankTrollman;468567If they are a "percentage of your chance to succeed", that would normally be a form of math. Of course, there are better ways to do that too. For example, rather than dividing your modified skill by 10 (or 5), just assign one number (or 2) in the ones place to be the critical threat. If you got the magic number and you succeeded, it's a crit.

It me, this is much harder as I have to look at the dice in two different ways: first as a percent, and second to see if some specific number came up on a specific die. With the standard Chaosium RQ method, I read the dice once as a percentage at glance at the table on my character sheet to tell me if I succeeded and how well. I don't think either method is intrinsically better. Which is better for an individual depends more on personal preferences than on anything else.

Quote from: RandallS;468573It me, this is much harder as I have to look at the dice in two different ways: first as a percent, and second to see if some specific number came up on a specific die. With the standard Chaosium RQ method, I read the dice once as a percentage at glance at the table on my character sheet to tell me if I succeeded and how well. I don't think either method is intrinsically better. Which is better for an individual depends more on personal preferences than on anything else.

No.

The math is so much of a pain in the ass that you don't even do it, and you look up the answers on a fucking chart. Special numbers in the ones place are so much better than that that it isn't even funny. Let's start with "however much space you just wasted on your fucking chart can be replaced with a bigger inventory box or pictures of naked ladies."

This is exactly the kind of bullshit grognardism that I am objecting to. The fact that you can get something to work at all and it is familiar to you and you fear change does not mean that it is "just as good" as doing it another way. It means that you have a personal problem where your fear of change is holding back actual progress.

-Frank

d100 roll over (the TN should be 101 to make it mathematically equivalent) involves adding two 2 digit numbers, probably resulting in a 3 digit number. That is a relatively slow operation. It's something that would be better done with a d20, and there is little that a d100 offers you over that.

Roll under is a simple comparison. If you need to do opposed checks then get one person to roll their score - the opponent's score +50. Adding modifiers makes very little difference.

If you want to use a d100, roll under will nearly always be preferred in play.

Quote from: spaceLem;468575d100 roll over (the TN should be 101 to make it mathematically equivalent) involves adding two 2 digit numbers, probably resulting in a 3 digit number. That is a relatively slow operation. It's something that would be better done with a d20, and there is little that a d100 offers you over that.

Roll under is a simple comparison. If you need to do opposed checks then get one person to roll their score - the opponent's score +50. Adding modifiers makes very little difference.

If you want to use a d100, roll under will nearly always be preferred in play.

Aaaargh!

Your suggestion for avoiding adding two digit numbers was to subtract two digit numbers. That's not easier.

-Frank

Quote from: spaceLem;468575(...)Roll under is a simple comparison. If you need to do opposed checks then get one person to roll their score - the opponent's score +50. Adding modifiers makes very little difference.(...)

It's not always clear who or what is the opponent. Also, what if more than two opponents are competing? Roll-over or blackjack method roll-under are much more practical for this.

Quote from: FrankTrollman;468574The math is so much of a pain in the ass that you don't even do it, and you look up the answers on a fucking chart.

Yes, getting rid of the math entirely so it doesn't matter how good or bad you are at math. Do the math once to create the table and you never need need to even think about it again -- better yet the table was created by the game designer so you don't even need to worry doing the math to create it.

Of course, there is a way to do it without tables and without much math (no math at all on most rolls) but having tried it is still slower and more effort than using a handy table.

Roll the dice. If the roll is over your percent chance you fail.  (No math).  If the roll is under your percent chance, you succeed.  (no math) If the roll is very low (at or under the tens digit of your percent chance, you have at least a special success -- it's a critical success if the roll is at or under half of the tens digit of your percent chance), otherwise it's a special success. (the only time you need math and it's simply taking half of a single digit number.

Side Note: IMHO, neither the roll under THAC0 or the roll over D20 hit roll (or any of the other variants, Target20, etc) is as easy for me as having the line for your character class and level from a old D&D "to hit" table on the character sheet. And I'm not bad at math, I just see no reason to do something over and over again when I can just glance at a table instead.

QuoteThis is exactly the kind of bullshit grognardism that I am objecting to. The fact that you can get something to work at all and it is familiar to you and you fear change does not mean that it is "just as good" as doing it another way. It means that you have a personal problem where your fear of change is holding back actual progress.

Or it means you are so in love with your preference that you can not grasp that what is best for you may not be best for someone else. (Or the many other things it might mean besides what you've assumed it means.)

BTW, I've been told my preferences for fast, abstract  combat (averaging 10 minutes, with around 20 minutes being the maximum I am willing to put up with) rather than the long combats with minis and battlemats of WOTC editions of D&D is "bullshit grognardism" as well. I don't apologize for not allowing others to force their pet ideas of what my gaming likes and dislikes should be on me -- or on my players. Nor will I adopt someone else's preferences just because they loudly and/or forcefully tell me over and over again how much theirs are great and mine are awful.

Quote from: Vile;468572Are there actually any games out there that use Roll-over D100 (given that I can't stand Rolemaster)?

I was curious enough about that to look over the rpg lists at Darkshire - not necessarily comprehensive as he doesn't always list core mechanic but outside of the Rolemaster family (RM/MERP/HARP) this turned up:
 
*100% Fantasy RPG, v1.00 (link seems to be dead) (freerpg)
*Bump in the Night RPG (attack rolls only; other checks are roll-low) (freerpg)
*OmniRole (freerpg, dead link)
*Tales of Wyn D'mere (listed as freerpg, dead link: also sold on drivethru though - I got a copy in the Haiti download).
 
Also:
-World of Synnibarr uses it for Shot (attack) Rolls (most other checks - including dodge rolls! - are roll under percentile);
-Legacy (game from 1978 about playing cavemen, by David A. Feldt) seems to have used it a bit.
 
 
StrikeForce: 2136 uses the subtraction method [skill - d100].
 
EDIT: Arduin Eternal (according to its review on rpgnet by ajadrakeh) uses d100+bonuses as well.

Hackmaster uses d100 roll over for opposed tests. They don't use for non-opposed tests "So they wouldn't be like d20". Seriously. They specifically chose to use extra baroque mechanics in order to not do things the way a more successful game did.

-Frank

Hrm, so no actual published games that use it as a core mechanism? Then it's either an untapped goldmine or just an unexploded mine. If anyone were to try to publish a mainstream game with it there had better be a whole damn lot of playtesting to try to break it in any which way that can be imagined, before going public.

That makes it unsuitable for re-working an old brand with established system expectations and a 6-month deadline. Still a contender for a daring entrepeneur, though.

Charts are good, but they are limited to what's on the chart. Also, for a complex long term game, a bountiful amount of charts get in the way and slow down the game considerably. If one is ok with that, that's fine. I happen to like charts a lot, and use them frequently, although try to limit the set of charts used to keep the game progressing at pace suitable for the story at hand.

I like the TN roll over system best though. It's elegant, it's simple, it's fast.

The d100 system offers a wider variety of options. The d20 system is faster, but offers less variety. Most actions in situations though don't require an option beyond succeed/fail, so why all the hullaballoo about using d100?

d100 does lend itself to extending the sweet spot in games where levels are used. With d100, level progression is slower, keeping the characters at low power levels (and vulnerable) longer while at the same time extending that mid-level interesting play phase and staving off the high-powered or over-powered level game that is the most difficult to balance for extended duration play.

Quote from: Vile;468588Hrm, so no actual published games that use it as a core mechanism?

Rolemaster uses it. Just because you don't like it doesn't mean it doesn't exist.

Personally, I find "roll under D100" to be very intuitive and simple.

I have played many different games over the years and none has come close to the simplicity of the generic d100 system. Well, HeroQuest does, but we'll gloss over that. :)

I can see how roll-over-100 works, but it isn't satisfying for me. I played Rolemaster a few times but didn't like it a lot - too many tables, disconnect between roll and damage, lost a dwarf tank in the first round of combat due to an arrow in the eye.

Quote from: FrankTrollman;468587Hackmaster uses d100 roll over for opposed tests. They don't use for non-opposed tests "So they wouldn't be like d20". Seriously. They specifically chose to use extra baroque mechanics in order to not do things the way a more successful game did.

-Frank

Define "More Successful"... ;)

For a Publisher "Successful" really means how much sell through the game does, i.e. how many copies sold vs how many got printed. Also, how much of a profit they made on it vs how much they spent developing it. So far, from all indicators that I've seen, HackMaster is doing very well and it's only been out for 2 years(the new version).

I don't see how the skill game mechanic is any harder than any other game system out there...

One situation in which roll-under systems work well is if there are few modifiers added to any particular roll. Openquest and UA are two roll-under systems in which you rarely modify target numbers or rolls, so it's a straight comparison between roll and target number with no math required. In OQ, you can even precalculate things for the few times you will get bonuses since they have a regular progression and narrow range (-50%, -25%, +25%, +50%).

MRQII, I'm finding, is about the tipping point - if I had to modify rolls more than I do when playing that game (about a third of the time) or if I needed to handle more than the addition of a single modifier regularly (less than 10% of the time), I'd look to simplify the math.

Roll-over would definitely improve Dark Heresy, WFRP, etc. where you're using tons and tons of modifiers and have extremely low skill percentages to begin with.

Good idea Frank, though I think you should look away from BRP for better examples of the possible convolutions of a roll-under percentile system, since BRP's overall tendency has been to simplify modifiers.

Quote from: danbuter;468591Rolemaster uses it. Just because you don't like it doesn't mean it doesn't exist.

Don't be the pedant, man. Unless you can follow it up with some actual useful information.

Quote from: Pseudoephedrine;468606Good idea Frank, though I think you should look away from BRP for better examples of the possible convolutions of a roll-under percentile system, since BRP's overall tendency has been to simplify modifiers.

I agree, I think BRP/RQ is better served by simplifying modifiers than turning the whole system around. I really only use skill x 1/2, skill x 1 or skill x 2. That's not hard (well, not for people I've gamed with). The main point is that a brand is only worth the name if it meets expectations, it's very risky to try to re-make the contents without losing the very thing that makes the brand valuable, i.e. its existing customer base.

Still very intrigued by this roll-over thing, though. I shall have to have a closer look at some of those games mentioned, even if they don't go the whole hog.

Roll under. More intuitive, no conversion math, and easier bookkeeping.

Whaddya gotta get to pass? You have a 75% chance, so roll inside that. OK! Done.

Hey, I got an extra point, what can I do with it? You can increase your 75% chance to 76%. OK! Done.

The only addition that makes my life easier is d100 ran by 2d10 read backwards & forwards. So an 81 reads also like an 18, so you'd get the minimum 1 success needed to pass. Also allows a degree of success function when I want it, too.

Roll-under D100 is probably the most intuitive mechanic of all.  In our regular lives we're constantly hearing shit like ·"45% of people will have suffered from a migraine in the past month", "you have a 30% chance of winning", "75% of dentists agree..", etc etc.

RPGPundit

Quote from: RPGPundit;468795Roll-under D100 is probably the most intuitive mechanic of all.  In our regular lives we're constantly hearing shit like ·"45% of people will have suffered from a migraine in the past month", "you have a 30% chance of winning", "75% of dentists agree..", etc etc.

RPGPundit

d100 roll over has the exact same quality. Your modifier is your chance of success, expressed as a percent.

-Frank

The problem with roll-under is thus: it reduces the granularity of the skill roll results to binary. Usually it does that by making the players announce the made their roll or failed. Any further info is lost in many, many cases.

Quote from: Settembrini;468809The problem with roll-under is thus: it reduces the granularity of the skill roll results to binary. Usually it does that by making the players announce the made their roll or failed. Any further info is lost in many, many cases.

Eh? BRP has special and critical successes, fumbles etc. Not binary at all.

Poppycock, in 90% of the cases, the player will announce "I made it/I failed."

Quote from: Settembrini;468819Poppycock, in 90% of the cases, the player will announce "I made it/I failed."

Considering there is usually a 10% chance of a special or critical result, you're right: about 90% of the time using the RQ/BRP system, the roll is going to be success or failure. That pretty much matches my experience in real life when I try something. I usually succeed or fail. Only on very rare occasions do I succeed (or fail) spectacularly.  

RQ/BRP isn't designed to present finely grained success or failure results because such are usually meaningless. I have 33 points of success climbing the cliff versus Joe who has 29 points of success. Geez, his foot must have slipped a couple of times more than mine did on the way up. In 99% of the situations, it doesn't matter at all. When it does, just subtract your die roll from your percent chance of success and you can have your finely grained result. No, it's not in the rules, but it is an obvious way to compare successes or failures at a very granular level on those rare occasions when it actually matters for anything but player ego boosting.

Quote from: FrankTrollman;468806d100 roll over has the exact same quality. Your modifier is your chance of success, expressed as a percent.

-Frank

Hehehe that is quite funny.....

the arguemtn being as pundit says you have a 45% chance of sucess so you roll under 45% and you succeed, the lower you get the better you suceeded.

Then Frank says but roll over is simple 'Your modifier is your chance of success, expressed as a percent' which still fails to tell us what you need to roll in any case.... so we can deduce that the target number is always 100% but its a deduction and i might be wrong and ask any person you like how best to express a 45 % change of doign it and they will say roll under 45....

Quote from: FrankTrollman;468806d100 roll over has the exact same quality. Your modifier is your chance of success, expressed as a percent.

-Frank

If the target number is 101, then yes, it has the same quality. If the target number is not 101, then no. For example, in Rolemaster, 101 is not the target number.

Quote from: Settembrini;468809The problem with roll-under is thus: it reduces the granularity of the skill roll results to binary. Usually it does that by making the players announce the made their roll or failed. Any further info is lost in many, many cases.

Except for those games that use a version of the BRP system, in which you have several categories of success. For example, in RQ3 you have critical success, special success, normal success, failure, and fumble. Not binary, I'm afraid.

Quote from: Settembrini;468819Poppycock, in 90% of the cases, the player will announce "I made it/I failed."

Except when the player gets a critical success, a special success, of a fumble.

So, according to you, roll-under is binary, except when it's not. :rolleyes:

It is obvious that mathematically there is no difference. In actual play practice, the difference is huge.

The cirticals are not margin of success and they are not modifier based. As both are mathematically equivalent, there is no reson to choose the roll under, as it is, communication-wise, inferior.

In roll-high (see what I did?), the player announces the number he achieved.

The dichotomy between roll under and roll over is false, as the true power of roll-high is to break out from the binary nature. Even with criticals, like in Harnmaster, roll under still reduced the dimension of results to 4, whereas roll-high is continous.

Ultimately the question comes down to the GMing practices of modifiers, and some roll-under proponents in this very thread have shown their colors there already.

Roll-under for me as well... intuitive and quick.

Quote from: Settembrini;468853As both are mathematically equivalent, there is no reson to choose the roll under, as it is, communication-wise, inferior.

Explain that bit please...

Rolemaster, BRP... I take both. They serve different purposes at the game table.

Quote from: Settembrini;468854Ultimately the question comes down to the GMing practices of modifiers, and some roll-under proponents in this very thread have shown their colors there already.

To me, the question comes down to why the heck should designers and players be forced to use "roll over" because you (and Frank) declare it "better"?

I prefer "roll under" for D100 system like RQ as it works better for me and most if the players I've played with. I don't care what works best for you and Frank. Neither of you play at my table.

IMHO, designers should be free to design as they and their target audience want -- not feel forced to use what someone has decided to decree as "best." Changing RQ to roll over would probably alienate as a large a percentage of RQ players as the changes in 4e alienated WOTC D&D players. Why should the RQ designers what to do this just to make the "roll over is always better" crowd happy?

Quote from: Simlasa;468875Explain that bit please...

Add degree of success or variable modifiers to the equation. You don't need to care about communication when you have a simple case, you need to worry about communication when you have a complex case.

When I succeed in Roll Over, I declare "134" and that means both that I succeeded and that I succeeded by 34 points. When I success in Blackjack, I declare "62, success", which tells the other players that my degree of success was 62, and that I succeeded. But I already gave two distinct pieces of information to get that across, and the information isn't even complete. Suppose that the GM suddenly remembers that the floor is covered in grease or something and I am operating at a -5 penalty.

In the Roll Over case, I've already given the GM the complete information. He just reduces 134 to 129 and says "Oh yeah, the floor is still greasy, so that's only a 29." But in the Blackjack setup he actually doesn't have complete information and has to ask more questions. "Oh yeah, the floor is still greasy, so you have an extra -5 penalty. Does a 62 still succeed?"

Do you get it now? You say more things and impart less information. And that actually matters once you engage in actions complex enough that you care about all the information.

-Frank

When I roll high in roll-high (see what i did there?), I announce "134" and actually do not know whether I suceeded or not. but I do know that everything over 100 is pretty good in standard cases. Whereas the reverse example...I do not know where to start.

As a player, I hate GMs who do roll-under, as they most of the time do not even care to modify die rolls at all. Personal, anecdotal, evidence.

I prefer roll-under.  d100 roll-over is just d20, and if I wanted to play d20, I'd play D&D.

Quote from: Settembrini;468901As a player, I hate GMs who do roll-under, as they most of the time do not even care to modify die rolls at all. Personal, anecdotal, evidence.

I've never had that problem -- either as a GM or as a player. My solution to it if I encountered it would be either to find a different GM or -- if the game was still a lot of fun anyway -- to just not care.  I would not see changing to roll over as a potential solution to poor GMing.  But then, I loathe rules changes to try to prevent poor GMing or poor playing.

Quote from: Settembrini;468901When I roll high in roll-high (see what i did there?), I announce "134" and actually do not know whether I suceeded or not. but I do know that everything over 100 is pretty good in standard cases. Whereas the reverse example...I do not know where to start.

As a player, I hate GMs who do roll-under, as they most of the time do not even care to modify die rolls at all. Personal, anecdotal, evidence.

Well, in fixed TN 100, you actually do know that you succeeded, barring opposed rolls or subsequently added modifiers. Fixed TN 100 is the case that is literally exactly the same as roll-under except that it has better inter-player communication.

Rolemaster is variable TN with roll-high. But if you fix the TN to 100, you get literally every single advantage of Roll-Under while still maintaining several of the roll-high advantages. So if we're going to be comparing Roll-high to Roll-low for d100, we're obviously going to be talking about the fixed TN 100 case.

Roll-under is very intuitive to design, since it is intuitively obvious that the numbers 01-57 represent 57% of the random number generator. But roll-high, fixed TN 100 has the same property. The numbers 43-99 also represent 57% of the RNG. So when you tell people that their skill is 57% and represents a 57% chance of success on an unmodified test, that stays the same. To the player, that advantage is held just as completely by roll-over-100 as it is by roll-under-skill. The designer had to do a little bit of math at the beginning to confirm the numerical identities, and that's why it doesn't get used much. But from the standpoint of the actual table, roll-over-100 is strictly superior in every way it isn't exactly the same.

-Frank

Quote from: FrankTrollman;468880In the Roll Over case, I've already given the GM the complete information. He just reduces 134 to 129 and says "Oh yeah, the floor is still greasy, so that's only a 29." But in the Blackjack setup he actually doesn't have complete information and has to ask more questions. "Oh yeah, the floor is still greasy, so you have an extra -5 penalty. Does a 62 still succeed?"

That's not how I see it come into play in a BRP game. It's rather :

GM : What are you doing?
Player: I play blackjack.
GM : Ok. Roll for it. The floor is still greasy though. That's a -5 penalty.
Player (looks at character sheet for blackjack skill) : 62. Success.

Perfect, now everybidy should be able to see it.

Quote from: Benoist;468955That's not how I see it come into play in a BRP game. It's rather :

GM : What are you doing?
Player: I play blackjack.
GM : Ok. Roll for it. The floor is still greasy though. That's a -5 penalty.
Player (looks at character sheet for blackjack skill) : 62. Success.

Blackjack is the system for generating degrees of success (DoS) in which the best roll is the highest number that still falls under your modified skill. It is not what BRP uses, but it is the best possible face that Roll-Under can put forward when resolving opposed rolls.

If you generate DoS in the blackjack method, and you have a 60% modified skill, then you have one number that generates a DoS of 59 (59) and one number that generates a DoS of 1 (01). If you generate DoS in the subtraction method, you still have one number that generates a DoS of 59 (01) and one number that generates a DoS of 1 (59). So it's mathematically the same. Blackjack proponents suggest it over roll-over because you are still able to figure your DoS with a comparison operation. Roll-under-skill with subtraction to determine DoS is obviously inferior to roll-over-100, because it's just subtracting double-digit numbers instead of adding them. The same mathematical operation, just slower and less accurate for human beings to do in real time.

So showing that the Blackjack method is inferior communicatively, which I did, is sufficient to show roll-over-100's inherent superiority. Roll-under-skill with subtractive DoS isn't even worthy of consideration.

-Frank

Right. That's why CoC is such a horriblibad game, and so many people played it over so many years. And RuneQuest. And Stormbringer. And Hawkmoon. And Nephilim. Etc. Right.

Call me when you come back from theoretical la-la-land down to the real world where people play games, Frank.

Quote from: Benoist;469027Right. That's why CoC is such a horriblibad game, and so many people played it over so many years. And RuneQuest. And Stormbringer. And Hawkmoon. And Nephilim. Etc. Right.

Call me when you come back from theoretical la-la-land down to the real world where people play games, Frank.

THAC0

-Frank

Quote from: FrankTrollman;469029THAC0

I don't see anything inherently wrong with THAC0 either. Like the arguments about with ascending or descending AC is the one best way, I just don't get it. Both work well. Some people like one more than the other, but that does not make the one you prefer inherently the best for every game and every player.

Translation: Just like there is no "One True Way" to play D&D, there is no "One True Way" to design RPGs.

Arbitrarily changing things in a well-known RPG like RQ just to match some designer's vision of "the one true way" is just going alienate players. If the rights to RQ fell into my lap, I certainly would not change the system to D100 roll over any more than I'd change the system in Rolemaster to D100 roll under if the rights to Rolemaster fell into my lap.  Both would upset lots of players without any real need for the change other than to match someone's "design theory."

Quote from: FrankTrollman;469029THAC0

-Frank

As far as I know, Call of Cthulhu, Stormbringer, etc, don't use THAC0. Do they?

Quote from: Benoist;468876Rolemaster, BRP... I take both. They serve different purposes at the game table.

This. I've played and enjoyed both.

Holy crap are you kidding? THAC0 was completely annoying, especially if you started getting into negative ACs (and what was up with that?!) Descending AC was more difficult and counter-intuitive in a number of ways. And those same issues are why Frank is so clearly and obviously right about d100 roll-over that I find it hard to believe this thread has gone on this long.

1) Addition is easier than subtraction. Some people don't have this problem, but most people I have encountered do. I certainly do.

2) As English speakers (and as far as I know, most or many other languages) ascending = better is ingrained into our language and thought process at a deep level, top ten countdowns notwithstanding. Roll higher = roll better is fundamentally intuitive to the way we think. Roll high but not more than X is better than roll low, but it's still a little weird and counter-intuitive.

3) GMs make mistakes and have to apply modifiers to the roll after the fact all the time, at least in my experience. The easier this is to do the better. If >100 is always a success, then this is an improvement over any system which varies the TN from roll to roll.

I get that Blackjack or Roll-low might be preferable for sentimental or aesthetic reasons, but roll-over is clearly simpler, clearer, and more intuitive.

Quote from: FrankTrollman;468959Roll-under-skill with subtraction to determine DoS is obviously inferior to roll-over-100, because it's just subtracting double-digit numbers instead of adding them. The same mathematical operation, just slower and less accurate for human beings to do in real time.

-Frank

I'll argue against THAC0 quite happily, but getting rid of roll under for d100 is a mistake. The most frequent thing you'll be doing is checking binary success/failure. In this case the ability to make a simple comparison with no addition involves makes it objectively superior. Situations where you have a large group of people shooting at each other become trivial with roll under.

When you add in degree of success, it becomes a weighting problem, as addition is easier than subtraction. Is it worth losing comparison for simpler DoS? I still feel that roll under wins (because it is very natural to say "I make the roll... by 12").

As for opposed rolls, roll over is indeed more natural. However, it's still a bloody awful mechanic, and the very worst of the roll and adds. About the only thing I like less than d100 roll over (apart from THAC0) is adding dice pools with more than 5 dice. I'd really consider switching to a d20, as you've lost the main thing a percentage system has going for it.

Quote from: FrankTrollman;469029THAC0

-Frank

You'll find no love for 2nd ed from me, technically speaking. And TSR drove DnD pretty much into the wall by the end of the 90s. THAC0 for me is a reference in the DMG, in first edition, and I pretty much don't use it in play. So. Shrug.

Quote from: Benoist;469027Right. That's why CoC is such a horriblibad game, and so many people played it over so many years. And RuneQuest. And Stormbringer. And Hawkmoon. And Nephilim. Etc. Right.

The trouble with that line of reasoning is that it only holds true if there isn't a single game, movie, boy band or other creative endeavor which, despite having a huge following, you still know to be totally worthless in your heart of hearts.

Let me see if I got this straight. Frank is advocating a solution for a problem that doesn't exist. It's very sad.

Quote from: Soylent Green;469051The trouble with that line of reasoning is that it only holds true if there isn't a single game, movie, boy band or other creative endeavor which, despite having a huge following, you still know to be totally worthless in your heart of hearts.

It's beyond that even, since people in the discussion aren't even saying that Roll-Under is bad or that it doesn't work. The proposition is merely that Roll-Over-100 is a better system.

If the proposition is "B is better than A" then the counter argument "A is good!" is not a counterargument at all. The argument "A is good enough!" is also not a counterargument. You haven't addressed the "B is better than A" proposition at all until you've actually shown some positive property that A has that B lacks or some negative property that B has that A lacks.

The "It was good enough in the late 1970s!" argument is simply a non sequitur. It is an incoherent response to the conversation. Blind grognardim in lieu of rational discourse. I'm not challenging the proposition that Roll-Under-Skill was good enough in the 1978. I'm not challenging the proposition that Roll-Under-Skill works at all. Seriously, those aren't being challenged. The challenge is merely that Roll-Over-100 is superior to Roll-Under-Skill. And the Roll-Under proponents haven't addressed that challenge at all.

-Frank

Quote from: FrankTrollman;469056Roll-Over-100 is superior to Roll-Under-Skill.

Except that it's not.

It is superiour, communication-wise. You remove at least one step, one time back and forth.

Also, several proponents of roll under are already on record in this very thread that they do not care for non-binary results. Now, if your preferences are such, than roll over does not differ from roll under indeed.

QuoteThe most frequent thing you'll be doing is checking binary  success/failure. In this case the ability to make a simple comparison  with no addition involves makes it objectively superior.

Q. to the fucking E. to the motherfucking D.

While I am in agreement that for percentile systems that frequently modify die rolls, roll-over is superior (especially in the case where degrees of success are currently calculated on the number of whole intervals of some value between roll and skill score like in WFRP and DH), there is one portion of conventional BRP-and-variants which would be a bigger hassle with a roll-over system, and that is calculating the roll required for a special success or a critical success.

So far as I can tell, the adaptation to roll-over would be to calculate one tenth (or one fifth) of the skill and then subtract that from 101 to get the roll above which one scores a critical.

This is more complicated than in regular BRP, where it is a straight comparison between the tens digit (or rarely hundreds and tens digits) and the die roll. I am curious if Frank and Sett have a proposal to simplify this.

Easy. make the Margin of succes your new indicator of criticality. Remember, dice tricks with numbers are only there to redeem the negative qualities of roll-under. With roll-over, you are free. Also, you can still do the HM-style multiples of five, so even that is saved.

QuoteQ. to the fucking E. to the motherfucking D.

QuoteEasy. make the Margin of succes your new indicator of criticality. Remember, dice tricks with numbers are only there to redeem the negative qualities of roll-under. With roll-over, you are free. Also, you can still do the HM-style multiples of five, so even that is saved.

You are an annoying cocksucker.  Just thought I'd throw that out there.

Quote from: Pseudoephedrine;469072While I am in agreement that for percentile systems that frequently modify die rolls, roll-over is superior (especially in the case where degrees of success are currently calculated on the number of whole intervals of some value between roll and skill score like in WFRP and DH), there is one portion of conventional BRP-and-variants which would be a bigger hassle with a roll-over system, and that is calculating the roll required for a special success or a critical success.

So far as I can tell, the adaptation to roll-over would be to calculate one tenth (or one fifth) of the skill and then subtract that from 101 to get the roll above which one scores a critical.

This has already been mentioned, but if you want to do 1/10th of successes or 1/5th of successes for crits like in WFRP or CoC, then you should be using magic numbers on the 1s die. You have one (or in CoC's case, two) numbers on the ones die that are critical numbers, and if you roll one and succeed, it's a critical.

You should be doing this anyway, because it's much faster and more likely to give the correct result than dividing your modified skill and running a second comparison operation.

-Frank

Well, I thought I could chime in and add some actual play experience with Frank's suggestions.

We've been using Frank's roll-over BRP modification in our CoC Delta Green game. for the last two sessions (more on that in another thread). By this I mean that now all rolls are 1d100+skill score vs a TN 100, and a special success is rolled when a successful roll has a 0 or a 5 in the units dice (so, a natural 65, 70, 75, etc). Opposed rolls (Spot Hidden vs Hiding and the like, or opposed characteristic rolls) are simple: highest roll wins for the same category of success. Yo fumble with 01, 01-02 if your skill is under 50%. That's it.

So far, we are liking this more than the usual roll-under. We don't have to do the addition for most rolls, as for simple rolls we usually can eyeball if it's above 100 or not, so it feels no different than a comparison. Critical success calculations are just a breeze, as it is the use of modifiers.

In the last scene yesterday there was a violent combat in a hotel room. In the first round we forgot many modifiers due to darkness and such, but we could easily add them because at my table dice rolls stand until next round in case we need to look them back.

Actually, one of my players said that he saw no reason to go back rolling under, because he hated to re-calculate special success chances due to modifiers (as if you have Gun 60% you make a special success with 01-12, but if something modifies your % you need to re-calculate it again).

Also, several of us are hardcore MERP players ;) One of them said we could use open rolls like in old MERP times :D

Overall, a very positive experience. We will probably keep using this roll-over variation. It has all the advantages of BRP and none of the disadvantages. You do not have to modify anything else, so you use the stat blocks as they are.

Definitely roll under, its quicker involved no maths and is used in most of may favourite games.

It is objectively NOT quicker. It involves more information that needs to be passed on from player to DM.

Quote from: Settembrini;469128It is objectively NOT quicker. It involves more information that needs to be passed on from player to DM.

In you games, maybe. I have played Rolemaster (roll-over) and RuneQuest (roll-under) and I know which one is quicker from personal experience, thank you very much. Objectively my ass.

Huh? Rolemaster involves tables and high rolls, all adding to length. Nothing to do with roll under.

On another front it bugs the hell out of me when players announce they made their rolls. How would they know? How should the GM interpret the result?

"I search the room!"
"Make a search check."
"I succeeded!"

The GM cannot be telling him the modifiers, as that would already give away too much info, i.e. that something is hidden there at all, as well as how good it is hidden.
Target numbers for the win.

Roll Under.

Definitely.

I don't want my Cthulhu players to fuck about with the mathematical bollocks that always seems to come with Roll-Over.

D.

Roll under with minimal modifiers and simple outcomes.

With roll over, every single roll includes adding two double digit rolls together and comparing them to a target number. It's d20 in treacle.

Quote from: Typhon;469136I don't want my Cthulhu players to fuck about with the mathematical bollocks that always seems to come with Roll-Over.

D.

I am very curious as to what you mean by that! Could you elaborate? Which mathematical bollocks?

Quote from: Settembrini;469132Huh? Rolemaster involves tables and high rolls, all adding to length. Nothing to do with roll under.

Rolemaster is roll-over, I said it myself.

My point is that I have played both roll-over and roll-under 1d100 systems, so I can judge from experience.

QuoteOn another front it bugs the hell out of me when players announce they made their rolls. How would they know? How should the GM interpret the result?

"I search the room!"
"Make a search check."
"I succeeded!"

The GM cannot be telling him the modifiers, as that would already give away too much info, i.e. that something is hidden there at all, as well as how good it is hidden.
Target numbers for the win.

You can do the same with roll under. The GM adds the modifier to the skill in his head, the player rolls, and only the GM knows if the PC succeeded.

Quote from: Claudius;469152You can do the same with roll under. The GM adds the modifier to the skill in his head, the player rolls, and only the GM knows if the PC succeeded.

Wow. So the player reports his modified skill and literal die roll? Wow... that's amazingly inferior to roll-over-100 as a system.

-Frank

Quote from: B.T.;468912d100 roll-over is just d20, and if I wanted to play d20, I'd play D&D.

Quote from: deleriad;469138With roll over, every single roll includes adding two double digit rolls together and comparing them to a target number. It's d20 in treacle.

I've seen this misconception crop out a few times, and it's about time to put it to rest. When the d20 system appeared, Rolemaster was already an old system. It's not that 1d100 roll-over is d20 in disguise, it's actually the other way around, d20 is 1d100 roll-over in disguise. D&D3 is in debt with Rolemaster, just like Rolemaster is in debt with AD&D. Before he wrote D&D3, Monte Cook wrote supplements for Rolemaster, that should give you a clue.

Quote from: FrankTrollman;469154Wow. So the player reports his modified skill and literal die roll? Wow... that's amazingly inferior to roll-over-100 as a system.

-Frank

No, the player reports his currect skill, it's the GM who adds the modifier.

Whereas with roll-over, you have to add two digit ciphers, which is always harder than just compare two numbers, which is what you do with roll-under.

Huh? So the GM rolls for the player?

QuoteWhereas with roll-over, you have to add two digit ciphers, which is  always harder than just compare two numbers, which is what you do with  roll-under.

Wait, there is substraction involved in roll-under, and that is scientifically proven to be more difficult for humans than addition. Also, the GM needs to remember three numbers, substract two and compare to one.

Whereas all the GM needs to do in roll-over is to compare to a target number,

I get the feeling we can safely say people who think roll-under is simpler are living in a self-fulfilling prophecy-world:

Doing away with modifiers, margin of success, hidden target number etc. is indeed simplification. As roll-under can do all of them only cumbersomely, they are done away with, and roll-under becomes very simple. The circle is closed.

Quote from: Settembrini;469157Huh? So the GM rolls for the player?

No, the player rolls, he just doesn't know what the target number is.

I used to be one of those GMs that sometimes rolled in secret (things like perception), but one day a player told me that he liked rolling the dice himself. Since then, they always roll the dice.

QuoteWait, there is substraction involved in roll-under, and that is scientifically proven to be more difficult for humans than addition. Also, the GM needs to remember three numbers, substract two and compare to one.

Whereas all the GM needs to do in roll-over is to compare to a target number,

It's true that substraction is generally harder than addition. However, when I run a 1d100 roll-under system, I only use multiples of ten as modifiers (-10, -20, -30, etc), they are not difficult at all.

Quote from: Settembrini;469158I get the feeling we can safely say people who think roll-under is simpler are living in a self-fulfilling prophecy-world:

I don't belong to that camp, I think they're equivalent.

QuoteDoing away with modifiers, margin of success, hidden target number etc. is indeed simplification. As roll-under can do all of them only cumbersomely, they are done away with, and roll-under becomes very simple. The circle is closed.

That's a strawman. When I run RuneQuest, I use modifiers, and margin of success. I don't use hidden target numbers, but I don't use them either when I run a roll-over system.

I think that the problem Frank and Settembrini have is that they are amongst a small niche group of players that are really interested in game mechanics  - a group of people in which I would include myself, I should point out. We like dissecting rules, and are thrilled – thrilled, I tell you! - by innovative and elegant new game mechanics.

The majority of players aren't like us. They aren't interested in the detail of the rules, don't read them (relying on people like Frank and Settembrini and me to plough through the rulebooks and explain how the game works). Above all else they don't want to have to relearn the rules once they have finally got the hang of them. This is the reason that, in the case of an existing game like RQ, roll under is superior to roll over: because the majority of people that play the game don't want to learn new rules, and would be happier if the designers were to leave them the way they are... well, as long as they work reasonably well, at least.  

In other words, and much as it pains an inveterate rules tinkerer like myself to admit it, the most important rule is: if it ain't broke (and in this case it ain't) don't fix it...

Glazer

The fact that I fail to see how roll-over is so much better than roll-under, doesn't mean I'm not interested in game mechanichs.

QuoteI've seen this misconception crop out a few times, and it's about time to put it to rest. When the d20 system appeared, Rolemaster was already an old system. It's not that 1d100 roll-over is d20 in disguise, it's actually the other way around, d20 is 1d100 roll-over in disguise. D&D3 is in debt with Rolemaster, just like Rolemaster is in debt with AD&D. Before he wrote D&D3, Monte Cook wrote supplements for Rolemaster, that should give you a clue.

What I'm saying is that why would I bother adding large numbers to get a three digit number when I could just roll 1d20 and have the same results?  If I have 1d20 + 10, it's the same as 1d100 + 50, but the numbers are smaller and thus faster to compute, making gameplay quicker and easier.

On a side note, people arguing about how 1d100 roll under is better than 1d100 roll over are retarded: roll over is superior in almost every way, as Frank has repeatedly explained.  My personal preference is roll under, but that doesn't mean that roll over isn't the superior system in terms of mathematical ease and intuitiveness.

The whole comparison completely neglects the psychological outlook of a human being on the numbers so far. That is, what the numbers might instinctively mean to him or her. Like say you have Climb 60%, roll under this value, versus Climb +60 roll over 100. There is a difference, and different players (and GMs) will react differently to these principles.

Quote from: B.T.;469175What I'm saying is that why would I bother adding large numbers to get a three digit number when I could just roll 1d20 and have the same results?  If I have 1d20 + 10, it's the same as 1d100 + 50, but the numbers are smaller and thus faster to compute, making gameplay quicker and easier.

Granularity. If you have played Rolemaster, MERP, or HARP (is there any other 1d100 roll-over system?), you can have a +53, or a +82. Sure, a d20 roll-over system is fine, just like a d20 roll-under system is fine too. Why would I want to play an 1d100 roll-under system, when I could play Pendragon (1d20 roll-under system)?

QuoteOn a side note, people arguing about how 1d100 roll under is better than 1d100 roll over are retarded:

Well, I'm not one of them. I like both roll-under and roll-over.

Quoteroll over is superior in almost every way, as Frank has repeatedly explained.  My personal preference is roll under, but that doesn't mean that roll over isn't the superior system in terms of mathematical ease and intuitiveness.

And I have repeatedly explained that that's not the case, that none of them is superior, it's just a question of taste.

Addition is quicker and easier than subtraction, but simple comparison is easier yet. So I find it difficult to say anything more decisive than "roll-over is better as long as you are habitually adding modifiers to skill rolls, often enough to offset the advantage of comparison vs. addition."

For me, roll over is tempting, but in practice I do not often modify skill rolls when I am GMing BRP. If a task is more difficult, I can have the PC apply the modifier by adding it to his roll, and if the raw roll is higher than the skill %, the addition can even be skipped. If the task is a markedly easy one, I would tend to ask myself if a roll is needed to begin with. I do not have a problem, by the way, with just telling the PC the modifier ahead of time and letting that influence his risk assessment. For something like Spot Hidden where the PC wouldn't know the modifier, I am going to be making the roll myself as GM anyway.

If I do add modifiers, I don't really see the point off modifying in less than 10% increments for situational modifiers to begin with. That kind of granularity can come in handy for fixed modifiers that have been figured in beforehand, advancement, etc., but on the fly I wouldn't bother with a 5% modifier. So it's really only a 1 digit of addition to begin with.

One place where roll-over seems clearly better is opposed rolls, rather than consulting a chart.

At least at a table I am personally running, I think I'd still see more overall benefit from roll-under comparison, but I might test out roll-over addition for the next BRP game I end up running. I wouldn't personally have a problem with using mostly roll-under comparison but calling for roll-over addition in certain circumstances (e.g. opposed rolls) as I saw fit, since they are basically equivalent, but I can see how you might want to pick one or the other for printed rules. I could see defaulting to roll-over and allowing a sidebar that offers comparison as a dirty trick for unmodfified checks, though.

Quote from: Imperator;469112Critical success calculations are just a breeze, as it is the use of modifiers.

How do you do critical successes?  5% or 10%?

Quote from: Imperator;469112In the first round we forgot many modifiers due to darkness and such, but we could easily add them because at my table dice rolls stand until next round in case we need to look them back.

If that's the rule, they would still be there in the case of roll-under too, right?

Quote from: Imperator;469112Actually, one of my players said that he saw no reason to go back rolling under, because he hated to re-calculate special success chances due to modifiers (as if you have Gun 60% you make a special success with 01-12, but if something modifies your % you need to re-calculate it again).

If you are using the Harn 0/5 method, you could use that for roll-under as well and not need to recalculate.

Quote from: Imperator;469112Also, several of us are hardcore MERP players ;) One of them said we could use open rolls like in old MERP times :D

Most of my players are RM/MERP aware at the least, and we've switched to roll-over for Dark Heresy (with a switch to d20 roll-over sometimes to allow for a fist full of auto-fire dice :D).

I'll try it for RQ, if the players go "Holy Shit! This is objectively and demonstrably superior!", we'll switch.  If they say "Meh, whatever.", we probably won't.

What about both? Roll under your skill and over a set difficulty. Kind of like blackjack.

Quote from: CRKrueger;469678How do you do critical successes?  5% or 10%?

In CoC, special successes are 1/5 of your %.

QuoteIf that's the rule, they would still be there in the case of roll-under too, right?

Guess so.

QuoteIf you are using the Harn 0/5 method, you could use that for roll-under as well and not need to recalculate.

Which method is that?

QuoteI'll try it for RQ, if the players go "Holy Shit! This is objectively and demonstrably superior!", we'll switch.  If they say "Meh, whatever.", we probably won't.

That is what we did, too. We decided to give it a couple sessions as a try, and this far we're very pleased.

Quote from: Imperator;469683In CoC, special successes are 1/5 of your %.

Are there also critical successes, or is that just BRP?

Quote from: Imperator;469683Which method is that?

It's the one you're using.  If a special success is defined as 20% of your normal success rate, then any success that ends in 0 or 5 is a special success.  As far as I know, that 0/5 method originated in Harnmaster.  It could be used for either over or under.

I think it really depends on the design of a game system as a whole. Roll-under and roll-over are just 2 tools a game designers arsenal. Roll-under puts some constraints on your numbers, but if your design fits within those parameters or has good reason to implement those constraints, you can have a very concise and intuitive game. Roll-over easily allows infinite escalation but it takes a more intricate framework of exceptions to contain.


D100 roll under is generally easier in practice. CoC is one of the simplest games ever to play. Characters are presumed to be within human standards of maximum aptitude. Their skills read as a % of the maximum. Resolution is supposed to be realistic and quick. The roll under system works wonders there by keeping the game simpler then it would be with a mathematically equivalent roll over system. As a whole it is very simple, intuitive and provides interesting games.

Some games do percentile bad. Like the FFG Warhammer 40k line. You need to add 20% to a skill when it is of 'average' difficulty. They want you to remember to add a number to your skill for the Majority of your rolls! That's pretty idiotic game design, even for a game made to simulate the oppressive universe of WH40k.

I haven't played any D100 roll-over games, none of the popular ones are appealing to me. I've read some version of Rolemaster and the massive list of tables turned me off completely.

With percentile, I prefer roll under. It's very easy to and quick to adjudicate. Same with most roll under systems actually. One quick comparison and your done. However, I would agree that roll-over is conceptually superior to roll-under. However, when  you throw a D100 before it, then you lose me. For a roll-over game to adequately take advantage of a D100 as it's core mechanic, it would need to be very petty and granular with the divvying up of bonuses and penalties. That's just something I'd rather not deal with.

Quote from: KrakaJak;469688Some games do percentile bad. Like the FFG Warhammer 40k line. You need to add 20% to a skill when it is of 'average' difficulty. They want you to remember to add a number to your skill for the Majority of your rolls! That's pretty idiotic game design, even for a game made to simulate the oppressive universe of WH40k.

This made me smile. The potential implication that someone out there designed an "oppressive universe" game to itself be oppressive, in play (for greater realism, don't ya know), is quite amusing.

And, like you, I've only played d100 as roll under. There doesn't appear to be anything fundamentally wrong with it, from the point of view of actual play. It could be that I'm missing out on some theory cred, mind you. ;)

Quote from: CRKrueger;469687Are there also critical successes, or is that just BRP?

The distinction between critical and special success comes from RQ, if I'm not mistaken.

QuoteIt's the one you're using.  If a special success is defined as 20% of your normal success rate, then any success that ends in 0 or 5 is a special success.  As far as I know, that 0/5 method originated in Harnmaster.  It could be used for either over or under.

Oh, definitely. For me, the main advantage of using roll-over is the ease of doing opposed - rolls, which I like to use a lot.

I'm not in favour of roll-over with percentile dice, since I like to know instantly the results when I roll the dice. It's okay to have addition and chart-consulting and so on, so long as they're before the dice-rolling. The dice-roll needs to be the money shot, once it happens it's all over, pass to the next player.

I tried the "roll dice, add modifiers, consult chart" for some years with Rolemaster, it got tedious. By the time we figured out if we'd lived or died we no longer cared.